JP2023167064A - fuel cell stack - Google Patents

Abstract

To provide a fuel cell stack which can reduce a variation in pressure loss of a reactant gas at a reactant gas inlet/outlet part and which can also ensure good adhesiveness between a pair of separators and a resin frame.SOLUTION: There is provided a fuel cell stack including a pair of separators and a resin frame. In a region where a first separator of one of the pair of separators has a reactant gas inlet/outlet part, a reactant gas inlet/outlet part of a second separator of the other of the pair of separators is not disposed. The resin frame has a three layer structure of a pair of adhesive layers and a core layer disposed between the pair of adhesive layers. In a region where the reactant gas inlet/outlet part is disposed, the pair of separators is bonded by the pair of adhesive layers of the resin frame. The pair of separators has second ribs that are convex in an opposite direction to a first rib at root portions on both sides of the first rib serving as a passage of the reactant gas inlet/outlet part.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to fuel cell stacks.

Various studies have been conducted regarding fuel cells.
For example, Patent Document 1 discloses a fuel cell separator that can prevent deformation even if a reaction force of a seal portion is applied to a fluid supply/discharge path of gas or the like of an intermediate plate, and does not cause pressure drop variations.

Japanese Patent Application Publication No. 2010-123510

In the prior art, it is necessary to insert a separate member as a reinforcing material in order to suppress variations in the pressure drop of the reactant gas due to deformation of the fuel cell. Furthermore, if another rigid member is inserted, the thickness of the fuel cell increases, resulting in an increase in the size of the fuel cell.
In a separator adhesive structure using a three-layer resin frame, there is a problem that during thermocompression bonding, the adhesive flows into the reactive gas inlet/outlet part, causing variations in the opening area of the reactive gas outlet/inlet part, resulting in variations in the pressure drop of the reactant gas, and There is a problem in that the thickness of the adhesive layer becomes thinner due to flow of the adhesive during thermocompression bonding, and sufficient adhesion between the pair of separators and the resin frame cannot be ensured.

The present disclosure has been made in view of the above-mentioned circumstances, and aims to reduce the occurrence of pressure drop variations in the reactant gas at the reactant gas lead-in/outlet portion, and to ensure good adhesion between a pair of separators and a resin frame. The main purpose is to provide a fuel cell stack that can.

In the present disclosure, there is provided a fuel cell stack having a cell stack in which a plurality of single cells are stacked, each including a pair of separators and a resin frame and a membrane electrode gas diffusion layer assembly disposed between the pair of separators. ,
The fuel cell stack has a reactant gas manifold,
The pair of separators have a reactive gas channel and a reactive gas inlet/outlet communicating with the reactive gas channel and the reactive gas manifold on the surface facing the membrane electrode gas diffusion layer assembly,
In a region where one of the first separators of the pair of separators has the reactive gas inlet/outlet, the reactive gas inlet/outlet of the other second separator is not arranged;
The resin frame has a three-layer structure including a pair of adhesive layers and a core layer disposed between the pair of adhesive layers,
In the region where the reaction gas inlet/outlet is arranged, the pair of separators are bonded by the pair of adhesive layers of the resin frame,
The pair of separators provides a fuel cell stack having second ribs protruding in a direction opposite to the first ribs at base portions on both sides of the first ribs, which serve as flow paths for the reactant gas introduction and inlet portions.

The fuel cell stack of the present disclosure can reduce the occurrence of pressure drop variations in the reactant gas at the reactant gas inlet/outlet portion, and can ensure good adhesion between the pair of separators and the resin frame.

FIG. 1 is a schematic plan view showing an example of the vicinity of a reaction gas manifold of a fuel cell stack according to the present disclosure when viewed from above. FIG. 2 is a schematic cross-sectional view showing an example of the AA cross section in FIG. FIG. 3 is a schematic cross-sectional view showing another example of the AA cross section in FIG.

Embodiments according to the present disclosure will be described below. Note that matters other than those specifically mentioned in this specification that are necessary for implementing the present disclosure (for example, the general configuration and manufacturing process of a fuel cell stack that do not characterize the present disclosure) are It can be understood as a matter of design by a person skilled in the art based on the prior art in the field. The present disclosure can be implemented based on the content disclosed in this specification and the common general knowledge in the field.
Furthermore, the dimensional relationships (length, width, thickness, etc.) in the figures do not reflect the actual dimensional relationships.
In this specification, "~" indicating a numerical range is used to include the numerical values written before and after it as the lower limit and upper limit.
Furthermore, any combination of upper and lower limits in the numerical range can be adopted.

In the present disclosure, there is provided a fuel cell stack having a cell stack in which a plurality of single cells are stacked, each including a pair of separators and a resin frame and a membrane electrode gas diffusion layer assembly disposed between the pair of separators. ,
The fuel cell stack has a reactant gas manifold,
The pair of separators have a reactive gas channel and a reactive gas inlet/outlet communicating with the reactive gas channel and the reactive gas manifold on the surface facing the membrane electrode gas diffusion layer assembly,
In a region where one of the first separators of the pair of separators has the reactive gas inlet/outlet, the reactive gas inlet/outlet of the other second separator is not arranged;
The resin frame has a three-layer structure including a pair of adhesive layers and a core layer disposed between the pair of adhesive layers,
In the region where the reaction gas inlet/outlet is arranged, the pair of separators are bonded by the pair of adhesive layers of the resin frame,
The pair of separators provides a fuel cell stack having second ribs protruding in a direction opposite to the first ribs at base portions on both sides of the first ribs, which serve as flow paths for the reactant gas introduction and inlet portions.

In the present disclosure, the adhesive of the pair of adhesive layers of the resin frame does not flow into the reactive gas flow path (groove) portion at the reactive gas inlet/outlet portion (comb tooth portion), and the adhesive side becomes a uniform surface, resulting in an appropriate thickness. The shape should be such that it can secure an adhesive layer. Specifically, a second rib that is convex in the opposite direction to the first rib is provided at the base of the first rib that serves as a flow path for the reaction gas introduction and inlet part, and when the pair of separators and the resin frame are bonded by thermocompression, Prevents adhesive from flowing into the reaction gas inlet/outlet. Thereby, it is possible to reduce the occurrence of variations in pressure drop of the reaction gas at the reaction gas lead-in/outlet portion, and to ensure good adhesion between the pair of separators and the resin frame.
Further, according to the present disclosure, it is possible to reduce the fluidity of the adhesive during thermocompression bonding between the pair of separators and the resin frame, so it is possible to improve the productivity of the fuel cell stack.

In this disclosure, the fuel gas and the oxidant gas are collectively referred to as a reaction gas. The reactive gas supplied to the anode is a fuel gas, and the reactive gas supplied to the cathode is an oxidant gas. The fuel gas is a gas mainly containing hydrogen, and may be hydrogen. The oxidant gas is a gas containing oxygen, and may be oxygen, air, dry air, or the like.

The fuel cell stack of the present disclosure has a cell stack in which a plurality of single cells are stacked, each including a pair of separators, a resin frame and a membrane electrode gas diffusion layer assembly disposed between the pair of separators.
In this disclosure, both a single cell and a fuel cell stack in which single cells are stacked may be referred to as a fuel cell.

The cell laminate is a laminate in which a plurality of single cells are stacked.
The number of stacked single cells in the cell stack is not particularly limited, and may be from 2 to several hundreds.

A single fuel cell cell includes a membrane electrode gas diffusion layer assembly (MEGA).
The membrane electrode gas diffusion layer assembly includes an anode gas diffusion layer, an anode catalyst layer, an electrolyte membrane, a cathode catalyst layer, and a cathode gas diffusion layer in this order.

The cathode (oxidant electrode) includes a cathode catalyst layer and a cathode side gas diffusion layer.
The anode (fuel electrode) includes an anode catalyst layer and an anode side gas diffusion layer.
The cathode catalyst layer and the anode catalyst layer are collectively referred to as a catalyst layer.
The catalyst layer may include, for example, a catalyst metal that promotes an electrochemical reaction, an electrolyte that has proton conductivity, a carrier that has electron conductivity, and the like.
As the catalyst metal, for example, platinum (Pt) and an alloy of Pt and another metal (for example, a Pt alloy mixed with cobalt, nickel, etc.) can be used.
The electrolyte may be a fluororesin or the like. As the fluororesin, for example, Nafion solution or the like may be used.
The catalyst metal is supported on a carrier, and in each catalyst layer, the carrier supporting the catalyst metal (catalyst-supporting carrier) and the electrolyte may coexist.
Examples of the carrier for supporting the catalytic metal include carbon materials such as carbon that are generally commercially available.

The cathode side gas diffusion layer and the anode side gas diffusion layer are collectively referred to as a gas diffusion layer.
The gas diffusion layer may be a conductive member or the like having gas permeability.
Examples of the conductive member include carbon porous bodies such as carbon cloth and carbon paper, and metal porous bodies such as metal mesh and foamed metal.

The electrolyte membrane may be a solid polymer electrolyte membrane. Examples of solid polymer electrolyte membranes include fluorine-based electrolyte membranes such as perfluorosulfonic acid thin films containing water, hydrocarbon-based electrolyte membranes, and the like. The electrolyte membrane may be, for example, a Nafion membrane (manufactured by DuPont).

The single cell includes a resin frame.
The resin frame has a three-layer structure including a pair of adhesive layers and a core layer disposed between the pair of adhesive layers.
The resin frame is arranged around the outer periphery of the membrane electrode gas diffusion layer assembly and between the cathode separator and the anode separator.
The resin frame may have a skeleton, an opening, and a hole.
The skeleton part is the main part of the resin frame connected to the membrane electrode gas diffusion layer assembly.
The opening is a holding area for the membrane electrode gas diffusion layer assembly, and is an area that penetrates a part of the skeleton to accommodate the membrane electrode gas diffusion layer assembly. The opening may be located in the resin frame at a position where the skeleton is located around the membrane electrode gas diffusion layer assembly (outer periphery), or may be located in the center of the resin frame.
The holes in the resin frame allow a fluid such as a reaction gas and a refrigerant to flow in the stacking direction of the unit cells. The holes in the resin frame may be aligned and arranged so as to communicate with the holes in the separator.
The core layer may have a frame shape, and the two adhesive layers provided on both sides of the core layer, that is, the first adhesive layer and the second adhesive layer, may also have a frame shape similar to the core layer. Good too. That is, the first adhesive layer and the second adhesive layer may be provided in a frame shape on both sides of the core layer, similarly to the core layer.

The core layer may be a structural member having gas sealing properties and insulating properties, and may be formed of a material whose structure does not change even under the temperature conditions during thermocompression bonding in the fuel cell manufacturing process. Specifically, the material of the core layer is, for example, polyethylene, polypropylene, PC (polycarbonate), PPS (polyphenylene sulfide), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PA (polyamide), PI ( polyimide), PS (polystyrene), PPE (polyphenylene ether), PEEK (polyether ether ketone), cycloolefin, PES (polyether sulfone), PPSU (polyphenylsulfone), LCP (liquid crystal polymer), epoxy resin, etc. It may also be made of resin or the like. The material of the core layer may be a rubber material such as EPDM (ethylene propylene diene rubber), fluorine rubber, silicone rubber, or the like.
The thickness of the core layer may be 5 μm or more, 30 μm or more from the viewpoint of ensuring insulation, and may be 100 μm or less, 90 μm or less from the viewpoint of reducing the cell thickness. It may be.

The first adhesive layer and the second adhesive layer have high adhesiveness with other substances and are used under the temperature conditions during thermocompression bonding in order to adhere the core layer and the anode separator and cathode separator to ensure sealing performance. The core layer may have a lower viscosity and melting point than the core layer. Specifically, the first adhesive layer and the second adhesive layer may be made of thermoplastic resin such as polyester or modified olefin, or may be made of thermosetting resin such as modified epoxy resin.
The resin constituting the first adhesive layer and the resin constituting the second adhesive layer may be the same type of resin or may be different types of resin. Providing adhesive layers on both sides of the core layer facilitates adhesion between the resin frame and the two separators by hot pressing.
The thickness of each of the first adhesive layer and the second adhesive layer may be 5 μm or more, or 30 μm or more, from the viewpoint of ensuring adhesiveness, and the thickness of the cell thickness may be 5 μm or more, or 30 μm or more. From the viewpoint of reduction, it may be 100 μm or less, or may be 40 μm or less.

In the resin frame, the first adhesive layer and the second adhesive layer may be provided only in the portions that adhere to the anode separator and the cathode separator, respectively. The first adhesive layer provided on one surface of the core layer may adhere to the cathode separator. The second adhesive layer provided on the other surface of the core layer may adhere to the anode separator. The resin frame may be sandwiched between a pair of separators.

The single cell includes a resin frame and a pair of separators that sandwich the membrane electrode gas diffusion layer assembly. One of the pair of separators is an anode separator and the other is a cathode separator. In this disclosure, an anode separator and a cathode separator are collectively referred to as separators.
The separator may have holes such as supply holes and discharge holes for allowing fluids such as reaction gas and refrigerant to flow in the stacking direction of the unit cells. As the refrigerant, for example, a mixed solution of ethylene glycol and water can be used to prevent freezing at low temperatures.
Examples of the supply hole include a fuel gas supply hole, an oxidant gas supply hole, a refrigerant supply hole, and the like.
Examples of the exhaust hole include a fuel gas exhaust hole, an oxidant gas exhaust hole, and a refrigerant exhaust hole.
The separator may have a reactive gas flow path on the surface in contact with the gas diffusion layer. Further, the separator may have a coolant flow path for keeping the temperature of the fuel cell constant on the surface opposite to the surface in contact with the gas diffusion layer.
The separator may have ribs forming channels such as a reaction gas channel and a coolant channel.
The separator may have ribs (hereinafter sometimes referred to as seal line ribs) that surround holes such as the supply hole and the discharge hole and are aligned with the seal line of the seal sheet on at least the surface on the refrigerant flow path side. The seal line rib may be arranged so as to surround holes such as the supply hole and the discharge hole when viewed from above, and may be arranged along the outer peripheral edge of the separator so as to surround all of these holes. It's okay. Moreover, the seal line rib may be arranged in alignment with the seal line of the seal sheet.
The anode separator may have a fuel gas flow path on the surface in contact with the anode side gas diffusion layer. Further, the anode separator may have a coolant flow path for keeping the temperature of the fuel cell constant on the surface opposite to the surface in contact with the anode side gas diffusion layer.
The cathode separator may have an oxidant gas flow path on the surface that contacts the cathode side gas diffusion layer. Further, the cathode separator may have a coolant flow path for keeping the temperature of the fuel cell constant on the surface opposite to the surface in contact with the cathode side gas diffusion layer.
The separator may be a gas-impermeable conductive member or the like. Examples of the conductive member include thermosetting resins, thermoplastic resins, resin materials such as resin fibers, carbon powder, and dense carbon made gas impermeable by compressing carbon materials such as carbon fibers. , a press-formed metal (for example, iron, aluminum, stainless steel, etc.) plate, etc. may be used. Further, the separator may have a current collecting function.
The shape of the separator may be a rectangle, a horizontally long hexagon, a horizontally long octagon, a circle, an oblong shape, or the like.

The pair of separators have a reactive gas channel and a reactive gas inlet/outlet communicating with the reactive gas channel and the reactive gas manifold on the surface facing the membrane electrode gas diffusion layer assembly.
The number of channels in the reactive gas inlet/outlet section is not particularly limited, and may be the same as the number of reactive gas channels.
The reaction gas inlet/outlet section connects the seal line rib of the separator, which is arranged to surround the reaction gas manifold in plan view, in the surface direction of the separator so that the reaction gas flow path (and gas distribution section) and the reaction gas manifold communicate with each other. It may be provided by penetrating it.
When the reaction gas flow path is an oxidant gas flow path, the reaction gas lead-in/out portion is an oxidant gas lead-in/out portion that communicates with the oxidant gas manifold, and when the reaction gas flow path is a fuel gas flow path, it is an oxidant gas lead-in/out portion that communicates with the oxidant gas manifold. This is a fuel gas inlet/outlet communicating with the manifold. The reactive gas lead-in/out part is a reactive gas introduction part when the reactive gas manifold is a reactive gas supply manifold, and is a reactive gas outlet part when the reactive gas manifold is a reactive gas discharge manifold.

The reactive gas lead-in/out part may be arranged in a predetermined region near the reactive gas manifold and on the membrane electrode gas diffusion layer assembly side of the reactive gas manifold in plan view.
In addition, in the region of the reaction gas manifold on the membrane electrode gas diffusion layer assembly side, the reaction gas lead-in/out section is connected to the reaction gas manifold side of the seal line rib of the separator in the seal line rib structure so as to cross the seal line in plan view. The reaction gas manifold and the reaction gas flow path may be arranged so as to penetrate both the side surface and the side surface on the side of the membrane electrode gas diffusion layer assembly in the surface direction of the separator to communicate with the reaction gas manifold.
The reaction gas manifold may have a region on the membrane electrode gas diffusion layer assembly side and a region on the side opposite to the region on the membrane electrode gas diffusion layer assembly side. The region on the side opposite to the region on the side of the membrane electrode gas diffusion layer assembly may be a region outside the unit cell in the plane direction.
The predetermined region of the region on the membrane electrode gas diffusion layer assembly side may be at least a part of the region on the membrane electrode gas diffusion layer assembly side.

The separator may have a gas distribution section that communicates with the reaction gas flow path and the reaction gas introduction/output section. The gas distribution section is disposed adjacent to the region of the reaction gas inlet/output section on the opposite side of the reaction gas manifold in the planar direction, and extends the gas flow from the reaction gas manifold to the power generation region or from the power generation region to the reaction gas manifold. This is the part that converges the gas flow. The gas distribution section has a structure that widens the gas flow on the inlet side of the reaction gas. The gas distribution section has a structure that converges the gas flow on the exit side of the reaction gas. The power generation area is an area where the membrane electrode gas diffusion layer assembly is arranged.

The fuel cell stack may have a manifold in which each hole communicates, such as a supply manifold with which each supply hole communicates, and an exhaust manifold with which each discharge hole communicates.
Examples of the supply manifold include a fuel gas supply manifold, an oxidant gas supply manifold, and a refrigerant supply manifold.
Examples of the exhaust manifold include a fuel gas exhaust manifold, an oxidant gas exhaust manifold, and a refrigerant exhaust manifold.
In the present disclosure, the fuel gas supply manifold and the oxidant gas supply manifold are collectively referred to as the reaction gas supply manifold.
In the present disclosure, the fuel gas exhaust manifold and the oxidant gas exhaust manifold are collectively referred to as the reaction gas exhaust manifold.
In this disclosure, the fuel gas supply manifold and the fuel gas discharge manifold are collectively referred to as the fuel gas manifold.
In the present disclosure, the oxidant gas supply manifold and the oxidant gas discharge manifold are collectively referred to as the oxidant gas manifold.
In the present disclosure, the fuel gas manifold and the oxidant gas manifold are collectively referred to as the reaction gas manifold.
In this disclosure, a refrigerant supply manifold and a refrigerant discharge manifold are collectively referred to as a refrigerant manifold.
A fuel cell stack has at least a reactant gas manifold and typically also has a coolant manifold.

The fuel cell stack may have a seal sheet between adjacent single cells.
The seal sheet is placed between adjacent single cells and is used as a sealing member for the adjacent single cells.
The seal sheet may be made of thermoplastic resin such as polyester-based or modified olefin-based resin, or may be made of thermosetting resin such as modified epoxy resin.
The seal sheet may have a frame shape. The frame serving as the seal line of the seal sheet may be aligned with the seal line rib of the separator. The seal sheet may have a shape that covers the entire surface of the separator except for the holes in the separator. That is, the seal sheet may cover the entire surface of the separator except for the holes in the separator.
The width of the frame serving as the seal line of the seal sheet may be the same as the width of the seal line rib of the separator, or may be larger than the width of the seal line rib of the separator.
The seal sheet is a seal that surrounds and seals the reactive gas manifold in plan view, crosses the reactive gas inlet/outlet of one of the pair of separators in plan view, and is disposed on the seal line rib of the separator. It may have a line.
The reactive gas manifold here may be a fuel gas manifold, an oxidant gas manifold, or both manifolds. The fuel gas manifold here may be a fuel gas supply manifold, a fuel gas discharge manifold, or both manifolds. The oxidant gas manifold here may be an oxidant gas supply manifold, an oxidant gas discharge manifold, or both manifolds.

In a region where one of the pair of separators, the first separator, has a reactive gas inlet/outlet, the reactive gas inlet/outlet of the other second separator is not arranged.
The pair of separators are bonded to each other by a pair of adhesive layers of the resin frame in a region where the reactive gas inlet/outlet portion is arranged.

In the first embodiment of the present disclosure, the pair of separators have second ribs that are convex in the opposite direction to the first ribs at the root portions on both sides of the first ribs, which serve as flow paths for the reaction gas introduction and inlet portions. .
The height of the second rib may be less than the height of the first rib.
By providing the second rib, it is possible to suppress the adhesive from flowing into the reaction gas inlet/outlet portion during thermocompression bonding between the pair of separators and the resin frame.

In the second embodiment of the present disclosure, in the region where the first separator has the reactive gas inlet/outlet, the second separator has the first rib in the region of the first separator that does not face the first rib of the reactive gas inlet/outlet. It may have a third rib that is convex in the same direction.
The height of the third rib may be less than the height of the first rib.
In the present disclosure, in the second separator facing the first separator having the reactive gas lead-in/outlet part with the resin frame in between, the same rib as the first rib is provided in a region not facing the first rib of the first separator having the reactive gas lead-in/out part. By providing a third rib that is convex in the direction, it is possible to prevent the adhesive from flowing out due to crushing of the adhesive layer during thermo-compression bonding between the pair of separators and the resin frame, and to ensure the thickness of the adhesive layer. can. The outside here means the outside of the area that becomes the bonding surface between the pair of separators and the resin frame.

In the third embodiment of the present disclosure, in the region where the first separator has the reactive gas inlet/outlet, the second separator has a region that does not face the first rib and the second rib of the reactive gas inlet/outlet of the first separator, It may have a third rib that is convex in the same direction as the first rib.

In the fourth embodiment of the present disclosure, in the region where the first separator has the reactive gas inlet/outlet part, the second separator has a second separator with a second It may have a third rib that is convex in the same direction as the first rib.
Ensuring the thickness of the adhesive layer by the third rib is effective even when the third rib is arranged to intersect with the flow path of the reaction gas inlet/outlet portion of the first separator in plan view.

FIG. 1 is a schematic plan view showing an example of the vicinity of a reaction gas manifold of a fuel cell stack according to the present disclosure when viewed from above.
As shown in FIG. 1, the first separator 20 has a reaction gas inlet/outlet part 21. As shown in FIG.
The reaction gas manifold 10 may be a fuel gas manifold or an oxidant gas manifold.
The fuel cell stack of the present disclosure may have a seal line 11 of a seal sheet that surrounds and seals the reaction gas manifold 10 in a plan view.

FIG. 2 is a schematic cross-sectional view showing an example of the AA cross section in FIG. Although only one single cell is shown in FIG. 2 for convenience, a plurality of single cells may be stacked.
As shown in FIG. 2, the single cells of the fuel cell stack of the present disclosure are arranged between the first separator 20 and the second separator 22 and between the first separator 20 and the second separator 22 in the vicinity of the reaction gas manifold 10. It has a resin frame 23.
The resin frame 23 has a three-layer structure including a first adhesive layer 24, a second adhesive layer 25, and a core layer 26 disposed between the pair of adhesive layers.
The first separator 20 has second ribs 31 that are convex in the opposite direction to the first ribs 30 at the root portions on both sides of the first ribs 30 that serve as flow paths for the reaction gas introduction/output portions 21 .
Thereby, it is possible to suppress the first adhesive layer 24 from flowing into the first rib 30 during thermocompression bonding between the pair of separators and the resin frame 23, and it is possible to ensure the thickness of the first adhesive layer 24. can.
In the region where the first separator 20 has the reactive gas inlet/outlet part 21, the second separator 22 does not have the reactive gas inlet/outlet part 21, and the first rib 30 and the second rib of the reactive gas inlet/outlet part 21 of the first separator 20 A third rib 32 that is convex in the same direction as the first rib 30 is provided in a region that does not face the third rib 31 .
As a result, it is possible to suppress the adhesive from flowing out to the outside due to crushing of the pair of adhesive layers when the pair of separators and the resin frame 23 are bonded by thermocompression, and it is possible to ensure the thickness of the pair of adhesive layers. can.
Note that in FIG. 2, the third rib 32 may be arranged in a region facing the second rib 31.

FIG. 3 is a schematic cross-sectional view showing another example of the AA cross section in FIG. In FIG. 3, the same components as in FIG. 2 are denoted by the same reference numerals, and their explanations will be omitted. Although only one single cell is shown in FIG. 3 for convenience, a plurality of single cells may be stacked.
As shown in FIG. 3, in the region where the first separator 20 has the reactive gas inlet/outlet part 21, the second separator 22 does not have the reactive gas inlet/outlet part 21, and the flow of the reactive gas inlet/outlet part 21 of the first separator 20 is It has a third rib 32 that is convex in the same direction as the first rib 30 in a direction intersecting the road direction (direction along the AA cross section in FIG. 3).
As a result, it is possible to suppress the adhesive from flowing out to the outside due to crushing of the pair of adhesive layers when the pair of separators and the resin frame 23 are bonded together by thermocompression, and it is possible to ensure the thickness of the pair of adhesive layers. can.

10 Reactive gas manifold 11 Seal line 20 First separator 21 Reactive gas lead-in/outlet section 22 Second separator 23 Resin frame 24 First adhesive layer 25 Second adhesive layer 26 Core layer 30 First rib 31 Second rib 32 Third rib

Claims (1)

A fuel cell stack having a cell stack in which a plurality of single cells are stacked, each of which includes a pair of separators, a resin frame disposed between the pair of separators, and a membrane electrode gas diffusion layer assembly,
The fuel cell stack has a reactant gas manifold,
The pair of separators have a reactive gas channel and a reactive gas inlet/outlet communicating with the reactive gas channel and the reactive gas manifold on the surface facing the membrane electrode gas diffusion layer assembly,
In a region where one of the first separators of the pair of separators has the reactive gas inlet/outlet, the reactive gas inlet/outlet of the other second separator is not arranged;
The resin frame has a three-layer structure including a pair of adhesive layers and a core layer disposed between the pair of adhesive layers,
In the region where the reaction gas inlet/outlet is arranged, the pair of separators are bonded by the pair of adhesive layers of the resin frame,
In the fuel cell stack, the pair of separators have second ribs protruding in a direction opposite to the first ribs at the root portions on both sides of the first ribs, which serve as flow paths for the reactant gas introduction/output portions.